[PATCH BlueZ 2/3] device: Add Role property

[Kevin Dewald <kevin@simpleble.org>]

This implements Role property using the initiator flag of the Device
Connected event, which the kernel sets when the adapter created the
connection as central, and emits PropertiesChanged when an LE
connection is added or removed.

Assisted-by: Claude:claude-opus-5.5
---
 src/device.c | 31 +++++++++++++++++++++++++++++++
 1 file changed, 31 insertions(+)

diff --git a/src/device.c b/src/device.c
index 1ab4e5342..1984b3e1c 100644
--- a/src/device.c
+++ b/src/device.c
@@ -1457,6 +1457,28 @@ static gboolean dev_property_get_connected(const GDBusPropertyTable *property,
 	return TRUE;
 }
 
+static gboolean dev_property_get_role(const GDBusPropertyTable *property,
+					DBusMessageIter *iter, void *data)
+{
+	struct btd_device *dev = data;
+	const char *role;
+
+	/* The initiator of an LE connection is always the central */
+	role = dev->le_state.initiator ? "peripheral" : "central";
+
+	dbus_message_iter_append_basic(iter, DBUS_TYPE_STRING, &role);
+
+	return TRUE;
+}
+
+static gboolean dev_property_exists_role(const GDBusPropertyTable *property,
+								void *data)
+{
+	struct btd_device *dev = data;
+
+	return dev->le_state.connected;
+}
+
 static gboolean dev_property_get_uuids(const GDBusPropertyTable *property,
 					DBusMessageIter *iter, void *data)
 {
@@ -3796,6 +3818,7 @@ static const GDBusPropertyTable device_properties[] = {
 	{ "CablePairing", "b", dev_property_get_cable_pairing },
 	{ "RSSI", "n", dev_property_get_rssi, NULL, dev_property_exists_rssi },
 	{ "Connected", "b", dev_property_get_connected },
+	{ "Role", "s", dev_property_get_role, NULL, dev_property_exists_role },
 	{ "UUIDs", "as", dev_property_get_uuids },
 	{ "Modalias", "s", dev_property_get_modalias, NULL,
 						dev_property_exists_modalias },
@@ -3944,6 +3967,10 @@ void device_add_connection(struct btd_device *dev, uint8_t bdaddr_type,
 	state->connected = true;
 	state->initiator = flags & BIT(3);
 
+	if (bdaddr_type != BDADDR_BREDR)
+		g_dbus_emit_property_changed(dbus_conn, dev->path,
+						DEVICE_INTERFACE, "Role");
+
 	if (dev->le_state.connected && dev->bredr_state.connected)
 		return;
 
@@ -4060,6 +4087,10 @@ void device_remove_connection(struct btd_device *device, uint8_t bdaddr_type,
 	state->initiator = false;
 	device->general_connect = FALSE;
 
+	if (bdaddr_type != BDADDR_BREDR)
+		g_dbus_emit_property_changed(dbus_conn, device->path,
+						DEVICE_INTERFACE, "Role");
+
 	device_set_svc_refreshed(device, false);
 
 	if (device->disconn_timer > 0) {
-- 
2.54.0 (Apple Git-157)